Methods and apparatus for filtering content in a video stream using closed captioning data

ABSTRACT

Various embodiments of apparatus and/or methods are described for skipping and/or filtering content from a video stream using closed captioning data associated with the video stream. The closed captioning data is parsed using metadata to identify portions of the video stream to skip during presentation, and/or to identify portions of the video stream to output to a user. The portions of the video stream that are to be skipped are filtered from the video stream, and the filtered video stream is presented to a user.

RELATED APPLICATIONS

This application claims the benefit of U.S. application Ser. No.11/942,111, entitled “METHODS AND APPARATUS FOR FILTERING CONTENT IN AVIDEO STREAM USING TEXT DATA”, filed on Nov. 19, 2007, which is herebyincorporated by reference in its entirety.

BACKGROUND

Digital video recorders (DVRs) and personal video recorders (PVRs) allowviewers to record video in a digital format to a disk drive or othertype of storage medium for later playback. DVRs are often incorporatedinto set-top boxes for satellite and cable television services. Atelevision program stored on a set-top box allows a viewer to performtime shifting functions, and may additionally allow a viewer to skipover commercial breaks and other portions of the recording that theviewer does not desire to watch. However, the user performs thisfunction manually, for example, using a fast forward button of a remotecontrol associated with the DVR. This manual fast forwarding is aninconvenience for the user. Further, manual fast forwarding by a useroften leads to inaccurate results, because the user may fast forwardpast portions of the recording they desire to watch, or may resumeplayback during the portion of the recording that they want to skipover.

BRIEF DESCRIPTION OF THE DRAWINGS

The same number represents the same element or same type of element inall drawings.

FIG. 1 illustrates an embodiment of an entertainment system.

FIG. 2 illustrates an embodiment of a content distribution system.

FIG. 3 illustrates an embodiment of functional components of the DVR ofFIG. 2.

FIG. 4 illustrates an embodiment of a satellite broadcast system.

FIG. 5 illustrates an embodiment of a cable television distributionsystem.

FIG. 6 illustrates an embodiment of a process for filtering a videostream based on text data.

FIG. 7 illustrates an embodiment of a process for filteringinterstitials from a video stream based on text data.

FIG. 8 illustrates the relationship between the variables of the segmentmetadata.

FIG. 9 illustrates an example of a metadata stream transmitted to a DVR.

FIG. 10 illustrates an embodiment of a process for creating segmentbookmarks of a recording.

DETAILED DESCRIPTION

The various embodiments described herein generally provide apparatus,systems and methods which facilitate the reception, processing, andoutputting of audio/video (A/V) content. In short, various embodimentsdescribed herein provide apparatus, system and/or methods for filteringcontent from a A/V stream based on data included in the A/V stream orassociated with the A/V stream.

In at least one embodiment, the A/V stream to be received, processed,outputted and/or communicated may come in any form of a video stream. Itis to be appreciated that the video stream may be supplied by anysource, such as an over-the-air broadcast, a satellite or cabletelevision distribution system, a digital video disk (DVD) or otheroptical disk, the internet or other communication networks, and thelike. In at least one embodiment, the video stream may include textdata, such as closed captioning data or subtitles, that is included inthe video stream or associated with the video stream. Thus, in at leastone embodiment, the video stream may comprise video data, audio data andtext data.

In various embodiments described herein, the text data correspondingwith an A/V stream is processed to identify portions of the A/V stream.An A/V stream will also be referred to herein as a video stream.However, it is to be appreciated that a video stream may include anassociated audio component. In at least one embodiment, the boundariesof the identified portions of the video stream may be indexed forutilization during presentation of the video stream. The portions of thevideo stream between indexed boundaries may then be designated forpresentation to a user, or may be designated for skipping duringpresentation of the video stream. Thus, in at least one embodiment,portions of a video stream that a user desires to view may be presentedto the user, and portions of the video stream that a user desires not toview may be skipped during presentation of the video stream.

FIG. 1 illustrates an embodiment of an entertainment system 100. Theentertainment system 100 presents content to a user 106. In at least oneembodiment, the content presented to the user 106 includes a videostream, such as a television program, movie or other recorded contentand the like. The entertainment system 100 includes a presentationdevice 102 and a content source 104. Each of these components isdiscussed in greater detail below.

The presentation device 102 is configured to receive content from one ormore content source(s) 104, and to present the received content to theuser 106. In at least one embodiment, the presentation device 102 is adisplay device configured to display content to the user 106. In otherembodiments, the presentation device 102 is a set-top box (e.g., asatellite or cable television converter box), digital video recorder(DVR) or other similar device that processes and provides one or moreaudio and/or video streams to a display device for presentation to auser. It is to be appreciated that the presentation device 102 may alsobe embodied as an apparatus combining the functionality of a displaydevice and a set-top box, DVR or the like.

The presentation device 102 may receive a video stream in any format(e.g., analog or digital format), and present the video stream to theuser 106. In at least one embodiment, the presentation device 102 mayfilter a received video stream to skip portions of the video stream.More particularly, in at least one embodiment, the presentation device102 may filter a video stream by identifying data in the video stream orassociated with the video stream that may be correlated with boundariesfor portions of the video stream. For example, the presentation device102 may parse the text data (e.g., the closed captioning data orsubtitles) for a video stream to identify the boundaries for variousportions of the video stream. In at least one embodiment, thepresentation device 102 may receive metadata including instructions forparsing the text data to identify the boundaries in the video stream.The identified boundaries may then be utilized for determining whichportions of the video stream will be presented to the user 106.

The content source 104 may comprise any system or apparatus configuredto provide presentation data, such as a video stream, to thepresentation device 102. The content source 104 may be external orinternal to the presentation device 102. The presentation device 102 andthe content source 104 may be communicatively coupled through any typeof wired or wireless connection, communication network and the like.Exemplary content sources include television distribution systems (e.g.,over the air distribution systems, cable television distributionsystems, satellite television distribution systems and broadbanddistribution systems), DVD players and other optical disk players,digital storage mediums (e.g., DVRs) and the internet. The video streamprovided by the content source 104 may include text data, such assubtitles or closed captioning data. The text data may be embedded inthe video stream (e.g., in vertical blanking interval line 21 or userdata) or may be provided in a separate data stream. In at least oneembodiment, the content source 104 may further provide metadata to thepresentation device 102 that is utilized for filtering of the videostream. The metadata is discussed in greater detail below. Thus, throughthe operation of the entertainment system 100, the user 106 is presentedwith a filtered version of a video stream. Entertainment system 100 mayinclude other elements or components not illustrated for the sake ofbrevity.

FIG. 2 illustrates an embodiment of a content distribution system 200.The content distribution system 200 is configured to present a filteredvideo stream to a user 106. The content distribution system 200 includesa DVR 202, a display device 204, a transmission network 206 and acontent provider 208. Each of these components is discussed in greaterdetail below.

The display device 204 may comprise any type of device operable forreceiving and displaying analog and/or digital video signals. In atleast one embodiment, the display device 204 may be a television set orvideo display that contains an integrated television converter device(e.g., an internal cable-ready television tuner housed inside atelevision), or, alternatively, that is connected to an externaltelevision converter device for receiving and demodulating analog and/ordigital signals for presentation on the display device 204 (e.g., aset-top box).

Using an integrated television converter device, the display device 204may be operable to communicate directly with the transmission network206. For example, the transmission network 206 may comprise anover-the-air distribution system (e.g., free television), and thedisplay device 204 may receive television broadcast signals using aninternal or external antenna. The transmission network 206 may alsocomprise a cable television distribution system, and the display device204 may comprise a cable ready television adapted to receive anddemodulate analog or digital cable television signals for presentationto the user 106. A direct broadcast satellite or other type of wired orwireless communications network may also be used solely or inconjunction with the foregoing. In at least one embodiment, the displaydevice 204 may communicate with the transmission network 206 through anintermediate device, such as a set-top box.

The DVR 202 is communicatively coupled to the display device 204 throughany type of wired or wireless connection. Exemplary wired connectionsinclude coax, fiber, composite video and high-definition multimediainterface (HDMI). Exemplary wireless connections include WiFi andBluetooth. In at least one embodiment, the DVR 202 may be embodied in atelevision converter device (e.g., a satellite television receiver). TheDVR 202 may also be incorporated into the display device 204.

The DVR 202 captures and records video content from attached devicesonto a storage medium for subsequent presentation to the user 106. Asillustrated in FIG. 2, the DVR 202 is coupled to a content provider 208(e.g., a satellite television provider) through the transmission network206. Thus, the DVR 202 receives a television signal (e.g., a broadcast)or other data signal (e.g., digital video data or other data formattedinto a video stream) from the transmission network 206, and recordstelevision programs and other content provided by the content provider208. The DVR 202 may perform processing functions to parse text dataassociated with or embedded in the video stream in order to filterportions of the video stream for presentation on the display device 204.It is to be appreciated that the DVR 202 may capture and record videostreams from other non-broadcast services, such as video recorders, DVDplayers, personal computers or the internet.

The DVR 202 may include a remote control or other input device (notshown) that the user 106 may utilize for remotely operating the DVR 202and/or the display device 204. More specifically, a remote control maybe operable for controlling the presentation of video and/or other datapresented by the DVR 202 on the display device 204.

The content provider 208 comprises any source or sources of televisionor other video signals. In at least one embodiment, the content provider208 provides a television broadcast signal to the DVR 202 over thetransmission network 206. The content provider 208 may provide closedcaptioning data with the television broadcast signal. The contentprovider 208 may be a television station that generates and provides thecontent or may be a television service that provides retransmission oftelevision signals (e.g., a satellite television provider). It is to beappreciated that the content provider 208 may also provide someretransmission services while generating and providing some original orderivative content.

The transmission network 206 may comprise any type of communicationnetwork utilized between the DVR 202 and the content provider 208.Exemplary communication networks include television distributionnetworks (e.g., over the air, satellite and cable television networks),wireless communication networks, public switched telephone networks(PSTN), and local area networks (LAN) or wide area networks (WAN)providing data communication services. The transmission network 206 mayutilize any desired combination of wired (e.g., cable and fiber) and/orwireless (e.g., cellular, satellite, microwave, and radio frequency)communication mediums and any desired network topology (or topologieswhen multiple mediums are utilized). The DVR 202 may communicate withthe transmission network 206 through a wired or wireless connection. Thetransmission network 206 may distribute television broadcast and otherdata signals in digital or analog form. Exemplary video formats includemoving picture expert group (MPEG), flash, Windows Media, and the like.Content distribution system 200 may include other elements or componentsnot illustrated for the sake of brevity.

FIG. 3 illustrates an embodiment of functional components of the DVR 202of FIG. 2. FIG. 3 will be discussed in reference to the contentdistribution system 200 illustrated in FIG. 2. The DVR 202 comprises areceiver 302, a recording module 304, a storage medium 306, a parsingmodule 308 and a presentation module 310. Each of these components isdiscussed in greater detail below.

The receiver 302 receives a video stream 312 and closed captioning data314 from the transmission network 206 (see FIG. 2). The receiver 302 maycomprise a wired or wireless receiver. In at least one embodiment, theclosed captioning data 314 is embedded within the video stream 312. Thereceiver 302 may further receive other data from the transmissionnetwork 206, such as metadata 316 instructing the DVR 202 how to parsethe closed captioning data 314 to determine boundaries within the videostream 312.

The recording module 304 receives the video stream 312 and the closedcaptioning data 314, and stores the video stream 312 and the closedcaptioning data 314 on the storage medium 306. The storage medium 306may be any type of temporary or persistent storage device capable ofstoring the video stream 312 and the closed captioning data 314. Thestorage medium 306 may be internal and/or external to the DVR 202 andmay include one or more storage devices. For example, the storage medium306 may be an internal hard drive or flash memory. The video stream 312and the closed captioning data 314 may be stored together and/orseparately on the storage medium 306.

The parsing module 308 is configured to index the closed captioning data314 according to a presentation order. In at least one embodiment, theparsing module 308 indexes the closed captioning data 314 during therecording process. In some embodiments, the parsing module 308 may indexthe closed captioning data 314 subsequent to recording. For example, theparsing module 308 may index the closed captioning data 314 uponreceiving a playback instruction from the user 106 (see FIG. 2). Theparsing module 308 is further configured to parse the closed captioningdata 314 to identify portions of the video stream to skip and/or presentduring presentation of the video stream 312 using the metadata 316 sentto the DVR 202.

The presentation module 310 is configured to present recorded videostreams to the user 106 (see FIG. 2). The presentation module 310retrieves the video stream 312 and/or the closed captioning data 314from the storage medium 306, and presents the content of the videostream 312 to the user 106 (see FIG. 2). In at least one embodiment, thepresentation module 310 receives information from the parsing module 308identifying portions of the video stream 312 that are to be skippedand/or shown during presentation. The presentation module 310 filtersthe video stream 312 to skip portions that are designated for skipping,and presents the filtered video stream 318 to the user 106 (see FIG. 2).In at least one embodiment, the presentation module 310 may removeportions of the video stream 312 that are designated for skipping. Ifapplicable, the presentation module 310 also presents the closedcaptioning data 314 corresponding to the portions of the filtered videostream 316 that are presented to the user 106.

Those of ordinary skill in the art will appreciate that the variousfunctional elements 302 through 310 shown as operable within the DVR 202may be combined into fewer discrete elements or may be broken up into alarger number of discrete functional elements as a matter of designchoice. For example, the parsing module 308, the recording module 304and/or the presentation module 310 may be combined into a singleprocessing module. Thus, the particular functional decompositionsuggested by FIG. 3 is intended merely as exemplary of one possiblefunctional decomposition of elements within the DVR 202.

FIG. 4 illustrates an embodiment of a satellite broadcast system 400.More particularly, FIG. 4 illustrates details of a transmission network206A. Satellite broadcast system 400 will be discussed in reference tocontent distribution system 200 illustrated FIGS. 2-3.

Satellite broadcast system 400 includes a content provider 208 in signalcommunication with an uplink system 402 of a transmission network 206A.The content provider 208 provides the uplink system 402 with televisionprograms that are transmitted to a DVR 202. Television programs may bebroadcast by the transmission network 206A to the DVR 202. Thetelevision program may be embodied as MPEG-2, MPEG-4 or other digitalvideo signals, analog or baseband signals, and/or other video data on achannel of the satellite broadcast system 400.

Satellite broadcast system 400 further comprises a satellite 404 insignal communication with the uplink system 402. The satellite 404broadcasts television programs received from the uplink system 402. Thesatellite broadcast system 400 further comprises a satellite antenna 406for receiving the television program broadcast from the satellite 404.The satellite antenna 406 is in signal communication with the DVR 202,and provides the DVR 202 with the television program. The broadcasttelevision program content is received and stored on the DVR 202, andmay be presented on the display device 204 responsive to the user 106selecting to view the recorded television program. The transmissionnetwork 206A may also be configured to transmit metadata and other datato the DVR 202. The metadata may be utilized by the DVR 202 to processthe television programming and filter out portions of the televisionprogramming.

In at least one embodiment, the DVR 202 may be configured to receiveover-the-air television programming from a transmitter 408 using a builtin receiver/tuner. For example, the DVR 202 may receive localprogramming over-the-air, and may receive national programming from thetransmission network 206A. In at least one embodiment, the DVR 202 mayreceive the metadata from the transmitter 408. In some embodiments, theDVR 202 may receive the metadata for the over-the-air programming fromthe content provider 208 through the transmission network 206A.

As illustrated in FIG. 4, the DVR 202 may optionally be communicativelycoupled to the content provider 208 through a broadband network 410using a broadband connection 412. The broadband connection 412 may beutilized to deliver metadata and/or video programming to the DVR 202. Itis to be appreciated that any combination of the described communicationpaths may be utilized to transmit video programming and/or metadatabetween the content provider 208 and the DVR 202. For example, the DVR202 may receive video programming through the transmission network 206A,and may request metadata associated with the video programming from thecontent provider 208 using the broadband network 410. It is also to beappreciated that the metadata and the video programming may be providedby difference sources (e.g., two different content providers 208).

Transmission network 206 (see FIG. 2) may also be embodied in a cabletelevision distribution system. FIG. 5 illustrates an embodiment of acable television distribution system 500. More particularly, FIG. 5illustrates details of a transmission network 206B. Cable televisiondistribution system 500 will be discussed in reference to contentdistribution system 200 illustrated in FIGS. 2-3.

Cable television distribution system 500 comprises a head-end 502 insignal communication with a content provider 208. The content provider208 provides the head-end 502 with television programs that aretransmitted to the display device 204. Television programs may bebroadcast by transmission network 206B, or may be pushed to the DVR 202responsive to a request by the user 106. Television programs may also bepushed to the DVR 202 using a broadband connection 412 through thebroadband network 410.

Cable television distribution system 500 further comprises a localdistribution network 504 in signal communication with the head-end 502.The local distribution network 504 is operable for receiving contentfrom the head-end 502 and distributing the content to individual displaydevices 204. The DVR 202 is in signal communication with the localdistribution network 504 using a drop 506 from a feeder line of thelocal distribution network 504. The local distribution network 504 mayprovide content as a broadcast to the DVR 202, or may provide content toa specific addressable DVR 202 using the broadband connection 412. In atleast one embodiment, the broadband network 410 may be integrated withinthe transmission network 206B.

FIG. 6 illustrates an embodiment of a process for filtering a videostream based on text data. The operation of FIG. 6 is discussed inreference to filtering a broadcast television program. However, it is tobe appreciated that the operation of the process of FIG. 6 may beapplied to filter other types of video stream content, such as DVDvideos. The operations of the process of FIG. 6 are not all-inclusive,and may comprise other operations not illustrated for the sake ofbrevity.

The process includes parsing text data associated with a video streamusing the metadata to identify portions of the video stream to skipduring presentation of the video stream (operation 602). Operation 602may be performed to skip portions of a video stream for a variety ofreasons. For example, a user may desire to skip commercials, portions ofa television program or other content which is of no interest to theuser, or portions of the video stream which are offensive or shouldotherwise not be shown to certain users. In at least one embodiment,operation 602 includes parsing the text data in the video stream that isdisplayable to a user.

In at least one embodiment, a video stream may include a recording of acontiguous block of programming from a television channel (e.g., anepisode of a television show). For example, a DVR may record a singlechannel between 7:00 and 8:00, which may correspond with a singleepisode of a television program. An hour long recording may includeapproximately 42 minutes of video frames of the television program, andapproximately 18 minutes of video frames of commercials and othercontent that is not part of the television program.

The television program may be comprised of multiple segments of videoframes, which are interspersed with interstitials (e.g., commercials).As used herein, an interstitial is the video frames of a recording thatdo not belong to a selected show (e.g., commercials, promotions, alerts,and other shows). A segment of video includes contiguous video frames ofthe program that are between one or more interstitials.

Illustrated in the table below is one exemplary breakdown of thesegments and interstitials within a recording of a one hour televisionprogram. For example, the recording may include six segments of theprogram, each including 7 minutes of video frames. Between each pair ofsegments is 3 minutes of interstitials. The beginning and ending of therecording includes 1.5 minutes of interstitials.

TABLE #1 Exemplary one hour television recording Portion of therecording Duration (mins) Interstitial #1 1.5 Segment #1 7 Interstitial#2 3 Segment #2 7 Interstitial #3 3 Segment #3 7 Interstitial #4 3Segment #4 7 Interstitial #5 3 Segment #5 7 Interstitial #6 3 Segment #67 Interstitial #7 1.5 Total duration 60

A string included within the text data may be utilized to identifyspecific locations within the video stream. The marked location may belocated within a portion of the video stream that is designated forpresentation (e.g., part of a television program), or may be within aportion of the video stream that is designated for skipping (e.g., in aportion of the program that a user does not desire to view).

For example, a string may identify a location within segment #1. Oncethe location is identified within segment #1, the boundaries of segment#1 may be determined. In at least one embodiment, the boundaries ofsegment #1 are identified using offsets relative to the identifiedlocation of a string. For example, if the identified location of thestring in segment #1 is 6 minutes into the, one hour recording, then anoffset of 4.5 minutes prior to the location of the string describes thebeginning of segment #1. Likewise, an offset of 2.5 minutes after thelocation of the string describes the ending of segment #1. A similarprocess may be utilized with additional strings and offsets to locatethe boundaries of the other segments of the video streams. In at leastone embodiment, multiple anchor frames, each having different startingand ending offset times, may be utilized within one segment forredundancy.

Thus, the parsing process identifies portions of the video stream thatare to be skipped during presentation to a user. In the exampleillustrated in table #1, operation 602 identifies interstitials #1-7 forskipping during presentation of the video stream. It is to beappreciated that other techniques may also be utilized to determine theboundaries of a segment once a location is identified by the parsingprocess. For example, a first string may be Utilized to identify thelocation of the beginning boundary of the segment, and a second stringmay be utilized to identify the location of the ending boundary of thestring.

Once the parsing process is complete, portions of the video stream maybe filtered prior to presentation. The process further includesfiltering the video stream based on the identified portions of the videostream (operation 604) to generate a filtered video stream. The processfurther includes presenting the filtered video stream to a user(operation 606).

As described above, interstitials #1-7 are designated for skippingduring the presentation of the video stream. Thus, segments #1-6 will bepresented to the user without the interstitials presented between eachsegment. The presentation of the television program will start at thebeginning of segment #1 (1.5 minutes into the recording), skipping thevideo frames of interstitial #1. After the ending of segment #1, thepresentation will continue at the beginning of segment #2. Therefore,the television user doesn't see the video frames of interstitial #2. Inat least one embodiment, an indicator, such as a small icon displayed ina corner of the screen, may be presented to a user to indicate that aportion of the video stream was skipped during the presentation.

FIG. 7 illustrates an embodiment of a process for filteringinterstitials from a video stream based on text data. The operation ofFIG. 7 is discussed in reference to filtering a broadcast televisionprogram. However, it is to be appreciated that the operation of theprocess of FIG. 7 may be applied to filter other types of video streamcontent. The operations of the process of FIG. 7 are not all-inclusive,and may comprise other operations not illustrated for the sake ofbrevity.

The process includes recording a video stream including at least onesegment of a show, at least one interstitial of the show, and closedcaptioning data associated with the segments of the show (operation702).

The process further includes receiving metadata associated with thevideo stream that identifies the boundaries of the segments of the show(operation 704). In at least one embodiment, for each segment of theshow, the metadata includes a string located within the segment, and abeginning and an ending offset from the string that identifies theboundaries of the segment. Offsets are utilized, because the actualpresentation times of the beginning and ending boundaries of the segmentmay change due to many factors, which are discussed in greater detailbelow. Operations 702 and 704 may be performed in parallel, orsequentially in either order. For example, the metadata may be receivedprior to recording the video stream, subsequently to recording the videostream, or at the same time as the video stream.

The process further includes indexing the closed captioning dataaccording to a presentation order (operation 706). Closed captioningdata is typically transmitted in two or four byte intervals associatedwith particular video frames. Because video frames don't always arrivein their presentation order, the closed captioning data is sortedaccording to the presentation order (e.g., by a presentation time stamp)of the closed captioning data. In at least one embodiment, the indexingprocess may be performed responsive to receiving the metadata in step704. Thus, a DVR may not perform the indexing process unless themetadata used to filter the video stream is available for processing. Inother embodiments, the closed captioning data may be indexed before themetadata arrives at the DVR. For example, the indexing may be performedin real-time during recording. In at least one embodiment, the sortedclosed captioning data is stored in a file and associated with therecorded video stream.

The process further includes processing the closed captioning data, tofilter the interstitials from the recorded video stream, based on themetadata, to generate a filtered video stream (operation 708). It is tobe appreciated that operation 708 may identify either the boundaries ofthe segments of the interstitials or the segments of the show to filterthe interstitials from the video stream.

In at least one embodiment, operation 708 may include creating segmentbookmarks that mark the start and end of a segment. A segment bookmarkis a structure created by the recording software. A start segmentbookmark points to the start of the segment, and an end segment bookmarkpoints to the end of a segment. The metadata for a segment includesinformation that specifies the boundaries of one segment. Morespecifically, in at least one embodiment, the metadata includes a string(which may be unique within the closed captioning data of the recording,or unique within the segments of the show), that is associated with ananchor frame. As used herein, an anchor frame refers to a video framethat contains selected bytes of a closed captioning string. In at leastone embodiment, the anchor frame contains the last bytes of the closedcaptioning string. It is to be appreciated that the anchor frame may bea show frame within the segment, or may be a skip frame within thesegment.

By locating the anchor frame, the beginning bookmark may be createdbased on the anchor frame and the beginning offset. Likewise, the endingbookmark may be created based on the anchor frame and the ending offset.The video frames between a beginning bookmark and an ending bookmark maydefine the portions of the video stream that are presented to a user.

The process further includes presenting the filtered video stream to auser (operation 710). If segment bookmarks are created, the presentationprocess includes presenting the segment of the video stream between thebeginning bookmark and the ending bookmark. Because the interstitialportions of the video stream are not included within the bookmarks for asegment, they are excluded from presentation to the user.

As described above, the actual presentation times of each segment of atelevision program within different recordings may vary. For example,two users may not begin recording a program at the same exact points ina broadcast. Thus, there may be a difference in the video framescontained within the recording made by each viewer. Also, manynationally televised shows are broadcast by affiliates of a broadcastnetwork. The broadcast network may have different affiliates in eachtelevision market around the country. Each affiliate has some discretionin the location of the interstitials of the television program, and isallowed to insert some of their own content (e.g., local commercials)into various portions of the time slot of the television program. Forexample, an affiliate may make one of the commercial breaks longer thancommercial breaks of other affiliates to accommodate a longer portion oflocal content, and likewise may make another commercial break shorter inorder to offset the difference. Thus, when a television program isrecorded in Denver, the recording may not be the same as a televisionprogram recorded in New York City.

Table #2 illustrates two exemplary break downs of interstitial andsegment durations for two different affiliates transmitting the sametelevision program in two different markets. The duration of eachsegment doesn't change, but the duration (and content) of eachinterstitial is different for the two affiliates. Table #3 illustratesexemplary segment and interstitial starting and ending times for eachaffiliate illustrated in FIG. 2. For example, viewers in NYC and Denvermay begin watching or recording a program at 7:00 in their respectivetime zones. The viewer in NYC will see the beginning of the firstsegment of the program at 1.5 minutes into the recording, while theviewer in Denver will see the beginning of the first segment of theprogram at 1 minute into the recording. Regardless of the starting timeof the segment, both viewers will see the same content of the segmentfor the seven minutes following the start of the segment.

TABLE #2 Exemplary one hour recording of a television program for twoaffiliates. Portion of program Duration (NYC) Duration (Denver)Interstitial #1 1.5 1 Segment #1 7 7 Interstitial #2 3 3 Segment #2 7 7Interstitial #3 3 4 Segment #3 7 7 Interstitial #4 3 3 Segment #4 7 7Interstitial #5 3 2.5 Segment #5 7 7 Interstitial #6 3 4 Segment #6 7 7Interstitial #7 1.5 0.5 Total duration 60 60

TABLE #3 Exemplary segment and interstitial starting and ending timesfor a recording from each affiliate. Start End Start End Portion ofprogram NYC Denver Interstitial #1 0 1.5 0 1 Segment #1 1.5 8.5 1 8Interstitial #2 8.5 11.5 8 11 Segment #2 11.5 18.5 11 18 Interstitial #318.5 21.5 18 22 Segment #3 21.5 28.5 22 29 Interstitial #4 28.5 31.5 2932 Segment #4 31.5 38.5 32 39 Interstitial #5 38.5 41.5 39 41.5 Segment#5 41.5 48.5 41.5 48.5 Interstitial #6 48.5 51.5 48.5 52.5 Segment #651.5 58.5 52.5 59.5 Interstitial #7 58.5 60 59.5 60

The process of FIG. 7 operates to identify an anchor frame within eachsegment of the television program. Beginning and ending offsets relativeto each anchor frame are then utilized to create beginning and endingbookmarks for the segment. Because the duration and content of eachsegment is the same, the beginning and the ending of the segment will bethe same offset relative to the anchor frame regardless of thepresentation times of the anchor frame. For example, an anchor frame forsegment #1 may be 2 minutes into the segment (relative to the beginningof the segment). In NYC, this means that the anchor frame has apresentation time of 3.5 minutes into the recording. However, in Denver,the anchor frame has a presentation time of 3 minutes into therecording. Beginning and ending offsets having the same duration arestill utilized in both markets, so the beginning bookmark for the NYCrecording is created at a presentation time of 1.5 minutes into therecording, and the beginning bookmark for the Denver recording iscreated at a presentation time of 1.0 minutes into the recording. Thus,each viewer skips over different duration interstitials #1, and beginsviewing the same frame of segment #1.

In at least one embodiment, the metadata that includes the strings andoffsets utilized to identify the boundaries of a segment may betransmitted to a DVR through a metadata stream and the like. The datathat identifies the boundaries of a segment is referred to herein assegment metadata. The show metadata, which may be delivered via ametadata stream, may include segment metadata for one or more segmentsof the show, and other information, such as the unique program ID (UPID)for the program. Each show may be identified by a UPID. A recording(e.g., one file recorded by a DVR between 7:00 and 8:00) may includemultiple UPIDs. For example, if a television program doesn't startexactly at the hour, then the DVR may capture a portion of a programhaving a different UPID. The UPID allows a DVR to associate a particularshow with its corresponding metadata.

Illustrated in table #4 is one exemplary format for segment metadatautilized by the processes of FIGS. 6-7. The segment metadata is carriedin the segment_descriptor( ) For error handling in the case of streamcorruption or censoring of offensive closed captioning by localaffiliates, multiple segment_descriptor( ) may be utilized for asegment. If there are multiple segment_descriptor( ) for a givensegment, then the segment_number will be the same for each but thecc_string[ ], start_offset, and end_offset will be different. Basically,alternate anchor frames may be specified for a given segment.

TABLE #4 Example of segment metadata structure. syntax no. of bitsmnemonic segment_descriptor( ) {  segment_tag 8 uimsbf  segment_length 8uimsbf  segment_number 8 uimsbf  last_segment_number 8 uimsbf cc_string_length 8 uimsbf  cc_string[ ] cc_string_length * 8 charstring  start_offset 32  uimsbf  end_offset 32  uimsbf }

segment_tag—0xC1

segment_length—The number of bytes in the segment_descriptor( ) afterthis field.

segment_number—A show normally consists of multiple segments. Thesegment metadata will be numbered 1 to N in time order (e.g., 1=first(earliest) segment, N=last (latest) segment).

last segment_number—The number of the last segment_number.

cc_string_length—The number of bytes in the closed captioning string(cc_string[ ]).

cc_string[ ]—The closed captioning bytes in presentation order (nottransmission order). The string may include all the bytes carried in avideo frame (2 or 4), and may include the bytes from multiple videoframes. The string may contain closed captioning bytes from enough videoframes to make the string unique within the segment.

start_offset—The number of presentation time stamps (PTS) ticks (1/90000s) from the anchor frame to the video frame that starts the segment. Thestart_offset points backwards in the recording from the anchor frame.

end_offset—The number of PTS ticks from the anchor frame to the videoframe that starts the interstitial immediately after the segment. Theend_offset points forward in the recording.

FIG. 8 illustrates the relationship between the variables of the segmentmetadata. However, it is to be appreciated the other exemplary dataformats may be utilized for the segment metadata. FIG. 9 illustrates anexample of a metadata stream transmitted to a DVR. Aprogram_unique_id_descriptor( ) uniquely identifies the show so that themetadata stream may be associated with the correct recording file. Thepackage type in the described example is “Show Metadata”.

In at least one embodiment, the DVR records an event, and monitors themetadata stream for “Show Metadata” metadata. If corresponding metadatais found, then the metadata is processed to create segment bookmarks forthe show. The segment bookmarks are then utilized to skip theinterstitials of the show.

The metadata stream carrying the show metadata may be delivered at anytime. Thus, the metadata stream may arrive at a DVR, before, during orafter a recording is made. If the metadata stream arrives at the DVRprior to an airing of the show, then the show metadata may be saved forfuture use should a user later decide to record the show. If a metadatastream arrives at the DVR after the show airs, then the DVR can processthe metadata stream to determine whether that particular show has beenrecorded. If the show has been recorded, then the DVR may beginprocessing the metadata stream to generate the segment bookmarks. If theshow has not been recorded, then the metadata stream may be discarded ifthe show metadata is not needed by the DVR.

In at least one embodiment, the metadata is stored on a server anddelivered responsive to a request from the DVR. For example, the DVR mayrequest the metadata from a server when it records a selected program.The metadata is then delivered to the DVR from the server and utilizedto parse the closed captioning data.

A DVR may index the closed captioning data before parsing the closedcaptioning data. Table 5 illustrates exemplary information utilized toindex the closed captioning data.

TABLE #5 Start code detector information Information Comments Size Thenumber of closed captioning bytes in the video frame (2 or 4). Closedcaptioning The undecoded (i.e., encoded) closed captioning (CC) bytesbytes in the video frame. PTS The PTS of the video frame that carriesthe closed captioning bytes. Offset The byte offset into the transportpacket stream to the first transport packet of the video frame thatcarries the closed captioning bytes.

In at least one embodiment, the DVR may filter the closed captioningstream and discard pairs of NULL (value=0×80) closed captioning bytes.There may be 2 or 4 closed captioning bytes per video frame. If theframe contains 2 closed captioning bytes, and both bytes are equal to0×80, then the bytes may be discarded and not saved. Otherwise, bothclosed captioning bytes are saved. If the frame contains 4 closedcaptioning bytes, and the first two bytes are equal to 0×80, then thefirst two bytes will be discarded and not saved. Otherwise, the firsttwo closed captioning bytes are saved. If the second two bytes are equalto 0×80, then the second two bytes are discarded and not saved.Otherwise the second two closed captioning bytes are saved. The DVR maysort the closed captioning stream so that the closed captioning bytesare in the presentation order. This is because the presentation order isutilized in the segment metadata. The PTS may be used to sort the closedcaptioning bytes into the presentation order.

The filtered and sorted closed captioning stream may be saved to astorage medium of the DVR, and associated with the recording of thevideo stream. Illustrated below is an exemplary array structure forstoring the filtered, sorted, and indexed closed captioning stream.However, it is to be appreciated that other storage structures may alsobe utilized.

struct cc_s { int n; // number of closed captioning bytes in the closedcaptioning buffer (2 or 4) u8 cc[4]; // the undecoded closed captioningbytes (unsigned char data type) s64 pts; // 33-bit PTS of the videoframe (long long data type) u64 offset; // zero-based (0 = 1st byte)offset into the recording };

As described above, segment bookmarks may be utilized to mark thebeginning and ending of a segment. Table #6 illustrates exemplaryinformation contained in the segment bookmarks. It is to be appreciatedhowever, that the segment bookmarks may contain other information thanlisted in table #6.

TABLE #6 Segment bookmark information Information Comments Start or Endflag Designates this bookmark as starting a segment or ending a segment,PTS The PTS of the video frame that starts/ends the segment. Offset Thebyte offset into the recording.

FIG. 10 illustrates an embodiment of a process for creating segmentbookmarks of a recording. The operation of FIG. 10 is discussed inreference to segment bookmarks for a television program. However, it isto be appreciated that the operation of the process of FIG. 10 may beapplied to create segment bookmarks for other types of video streamcontent. Further, the operations of FIG. 10 are discussed in referenceto particular data structures illustrated above. It is to beappreciated, however, that the operations of FIG. 10 may be utilized inaccordance with any types of data structures and other suitable types ofdata. The operations of the process of FIG. 10 are not all-inclusive,and may comprise other operations not illustrated for the sake ofbrevity.

After recording a show, an index of the closed captioning data for theshow and the show metadata associated with the program is processed tocreate segment bookmarks for each segment of the show. In at least oneembodiment, the show metadata is processed in segment_number order, 1 toN, to create the segment bookmarks for the show.

The process includes selecting a string from the metadata for use inidentifying a segment (operation 1002). This is selected from asegment_descriptor( ) The process further includes matching thecc_string[ ] from the segment_descriptor( ) to the closed captioningbytes in the index of the closed captioning data (operation 1004). If amatch is found, then the video frame indexed by the closed captioningdata is designated as the anchor frame (operation 1006). If a match isnot found, then an alternate segment_descriptor( ) if one exists, may beutilized to select an alternate anchor frame (operation 1008), andprocessing continues at operation 1004. The show metadata may includemultiple segment_descriptor( ) in case there are transmission problemswith the closed captioning data. For example, if one or more closedcaptioning bytes transmitted by a content provider are not received by aDVR, then a match of a segment_descriptor( ) may not be found. Thus, analternate segment_descriptor( ) may be utilized to locate an alternateanchor frame in the segment.

The process further includes determining the PTS of the selected anchorframe (operation 1010). The PTS may be determined from either the videostream, or through the closed captioning data index file. The processfurther includes creating the beginning bookmark of the segment(operation 1012). The PTS of the video frame at the start of the segmentis determined by taking the PTS of the anchor frame and subtracting thestart_offset from the segment_descriptor( ). The beginning bookmarkpoints to the PTS of the video frame at the start of the segment. Theprocess further includes creating the ending bookmark of the segment(operation 1014). The PTS of the video frame at the end of the segmentis determined by taking the PTS of the anchor frame and adding theend_offset from the segment_descriptor( ). The ending bookmark points tothe PTS of the video frame at the end of the segment. In at least oneembodiment, modulo arithmetic is utilized to handle cases where the PTSrolls. The segment bookmarks may be created once, and utilized multipletimes if the user desires to watch a program on more than one occasion.The operations of the process of FIG. 10 are repeated for any remainingsegments (e.g., any remaining segment_descriptor( ) fields for segmentsthat have not been processed).

Although specific embodiments were described herein, the scope of theinvention is not limited to those specific embodiments. The scope of theinvention is defined by the following claims and any equivalentstherein.

What is claimed is:
 1. A method for filtering a video stream, the methodcomprising: receiving a video stream including at least one segment of ashow, at least one interstitial of the show, and closed captioning dataassociated with the video stream; receiving metadata referencing theclosed captioning data to identify at least one anchor frame within thevideo stream, the metadata comprising a displayable text string includedwithin the closed captioning data as originally transmitted by a contentprovider, a first offset, relative to the anchor frame, that identifiesa beginning of the at least one segment, a second offset, relative tothe anchor frame, that identifies an ending of the at least one segment;parsing the closed captioning data associated with the video stream tolocate the anchor frame corresponding with the presentation of thedisplayable text string located in the closed captioning data recorded;identifying the boundaries of the at least one segment of the show basedon the anchor frame and the first and second offsets; filtering the atleast one interstitial from the video stream based on the identifiedboundaries to generate a filtered video stream; and outputting thefiltered video stream for presentation to a user.
 2. The method of claim1, wherein the anchor frame is associated with a presentation locationof the last two bytes of the displayable text string in the videostream.
 3. The method of claim 1, wherein parsing the closed captioningdata associated with the video stream further comprises: indexing theclosed captioning data according to a presentation order to generateindexed closed captioning data; discarding null closed captioning bytesfrom the indexed closed captioning data; and parsing the indexed closedcaptioning data to identify the anchor frame.
 4. The method of claim 1,further comprising: creating a beginning bookmark, identifying thebeginning of the at least one segment, based on the anchor frame and thefirst offset; and creating an ending bookmark, identifying the ending ofthe at least one segment, based on the anchor frame and the secondoffset.
 5. The method of claim 4, wherein creating the beginning andending bookmarks is performed responsive to receiving the metadata, themethod further comprising: receiving a request to view the video stream,subsequent to creation of the beginning and ending bookmarks; andoutputting the filtered video stream responsive to the request.
 6. Themethod of claim 1, wherein the displayable text string is unique withinthe text data.
 7. A method for filtering a video stream, the methodcomprising: receiving a video stream including first and second segmentsof a show, at least one interstitial of the show temporally positionedbetween the first and second segments, and closed captioning dataassociated with the video stream; receiving metadata referencing theclosed captioning data to identify first and second anchor frames withinthe video stream, the metadata comprising first and second displayabletext strings included within the closed captioning data as originallytransmitted by a content provider; parsing the closed captioning dataassociated with the video stream to locate the first anchor framecorresponding with the presentation of the first displayable text stringlocated in the closed captioning data recorded; identifying firstboundaries of the first segment of the show based on the first anchorframe and the metadata; parsing the closed captioning data associatedwith the video stream to locate the second anchor frame correspondingwith the presentation of the second displayable text string located inthe closed captioning data recorded; identifying the second boundariesof the second segment of the show based on the second anchor frame andthe metadata; filtering the at least one interstitial from the videostream based on the first boundaries and the second boundaries togenerate a filtered video stream; and outputting the filtered videostream for presentation to a user.
 8. The method of claim 7, wherein themetadata further comprises a first offset, relative to the first anchorframe, that identifies a beginning of the first segment, a secondoffset, relative to the first anchor frame, that identifies an ending ofthe first segment, wherein identifying the first boundaries furthercomprises: identifying a beginning boundary of the segment, based on theanchor frame and the first offset; and identifying an ending boundary ofthe segment, based on the anchor frame and the second offset.
 9. Themethod of claim 7, wherein the anchor frame is associated with apresentation location of the last two bytes of the displayable textstring in the video stream.
 10. The method of claim 7, wherein parsingthe closed captioning data associated with the video stream furthercomprises: indexing the closed captioning data according to apresentation order to generate indexed closed captioning data;discarding null closed captioning bytes from the indexed closedcaptioning data; and parsing the indexed closed captioning data toidentify the anchor frame.
 11. The method of claim 7, furthercomprising: creating a beginning bookmark, identifying the beginning ofthe at least one segment, based on the anchor frame and the firstoffset; and creating an ending bookmark, identifying the ending of theat least one segment, based on the anchor frame and the second offset.12. The method of claim 7, wherein creating the beginning and endingbookmarks is performed responsive to receiving the metadata, the methodfurther comprising: receiving a request to view the video stream,subsequent to creation of the beginning and ending bookmarks; andoutputting the filtered video stream responsive to the request.
 13. Themethod of claim 7, wherein the displayable text string is unique withinthe text data.
 14. A digital video recorder comprising: a receiver thatreceives a video stream including at least one segment of a show, atleast one interstitial of the show, and closed captioning dataassociated with the video stream, and receives metadata referencing theclosed captioning data to identify at least one anchor frame within thevideo stream, the metadata comprising a displayable text string includedwithin the closed captioning data as originally transmitted by a contentprovider; a recording module that stores the video stream on a storagemedium for subsequent presentation to a user; a parsing module thatparses the closed captioning data associated with the video stream tolocate the anchor frame corresponding with the presentation of thedisplayable text string located in the closed captioning data recorded,identifies the boundaries of the at least one segment of the show basedon the anchor frame and the first and second offsets; and a presentationmodule that filters the at least one interstitial from the video streambased on the identified boundaries, and that outputs the filtered videostream to the user.
 15. The digital video recorder of claim 14, whereinthe anchor frame is associated with a presentation location of the lasttwo bytes of the displayable text string in the video stream.
 16. Thedigital video recorder of claim 14, wherein the parsing module isfurther operable to: index the closed captioning data according to apresentation order to generate indexed closed captioning data; discardnull closed captioning bytes from the indexed closed captioning data;and parse the indexed closed captioning data to identify the anchorframe.
 17. The digital video recorder of claim 14, wherein the parsingmodule is further operable to: create a beginning bookmark, identifyingthe beginning of the at least one segment, based on the anchor frame andthe first offset; and create an ending bookmark, identifying the endingof the at least one segment, based on the anchor frame and the secondoffset.
 18. The digital video recorder of claim 17, wherein the parsingmodule creates the beginning and ending bookmarks responsive toreceiving the metadata and the presentation module is configured to:receive a request to view the video stream, subsequent to creation ofthe beginning and ending bookmarks; and output the filtered video streamresponsive to the request.
 19. A digital video recorder comprising: areceiver that receives a video stream including at least one segment ofa show, at least one interstitial of the show, and closed captioningdata associated with the video stream, and that receives metadatareferencing the closed captioning data to identify first and secondanchor frames within the video stream, the metadata comprising first andsecond displayable text strings included within the closed captioningdata as originally transmitted by a content provider; a recording modulethat stores the video stream on a storage medium for subsequentpresentation to a user; a parsing module that parses the closedcaptioning data associated with the video stream to locate the firstanchor frame corresponding with the presentation of the firstdisplayable text string located in the closed captioning data recorded,identify a beginning boundary of the interstitial based on the firstanchor frame and the metadata, parse the closed captioning dataassociated with the video stream to locate the second anchor framecorresponding with the presentation of the second displayable textstring located in the closed captioning data recorded and identify anending boundary of the interstitial based on the second anchor frame andthe metadata; and a presentation module that filters the at least oneinterstitial from the video stream based on the beginning and endingboundaries, and that outputs the filtered video stream to the user. 20.The digital video recorder of claim 19, wherein the first anchor framecomprises a video frame within the first segment and the second anchorframe comprises a video frame within the second segment.